(Actual: 4.75⭐, rounded up) Thank you to NetGalley and the publisher(s) for the eARC in exchange for an honest review and/or promotion. I loved this book! The cover (and the title tbh) were what immediately drew me into requesting this ARC, and I'm so, so happy I didn't leave from it disappointed. I love emotional, character-driven stories where yes, the plot matters of course— but it's not the Most Important Thing™, you know? And I feel like toeing that line can be especially tricky when it falls under a genre such as Science Fiction. Which is why this book, to me, succeeds in fitting that bill almost exactly. Mercury is fast-paced, aesthetically pleasing, and atmospheric in how it presents itself to us as the reader; it even has illustrations woven in throughout, which I really appreciated. This book tackles topics related to the inner turmoil we all face regarding making difficult decisions, rebelling against authority, and sorting through complicated interpersonal familial & social relationships. It's a quick read (less than 300 pages) with an open-ending that leaves room for a possible Part 2 should the author choose to go that route. As it stands however, when reviewing this book though at its face value - meaning, as a standalone story - I still found the end to be satisfying enough for me to walk away without nitpicking too much. If I had to critique anything , I would say that I wish it were longer so that certain scenes could be expanded on more fully (we all know I'm a lover of showing rather than simply telling), but again, I still enjoyed myself and would honestly recommend this to anyone looking for something unique to read.